<div class="btn-group btn-group-justified" role="group" aria-label="...">
	<div class="btn-group" role="group">
		<button type="button" class="btn btn-<?= a == 'book' ? 'primary':'default'?>"
		onclick="location.href='__URL__/book/'">班次</button>
	</div>
	<div class="btn-group" role="group">
		<button type="button" class="btn btn-<?= a == 'sign' ? 'primary':'default'?>"
		onclick="location.href='__URL__/sign/'">报到</button>
	</div>
	<div class="btn-group" role="group">
		<button type="button" class="btn btn-<?= a == 'line' ? 'primary':'default'?>"
		onclick="location.href='__URL__/line/'">统计</button>
	</div>
</div>

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